Shader nodes: ignore scaling, keep rotation
It sounds as if you should be using Texture Coordinate &gt; Object space.
This is in Blender units, from the object's origin, and in the orientation of the object's axes.
Be aware, that space carries the object's scale transform as well; to make sense, the object's scale will have to be (1,1,1).. (i.e. applied).
There's an example of a procedural wood here